36082260 knit fabric processing[1]

8/6/2019 36082260 Knit Fabric Processing[1]

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INTERNSHIP REPORT

ON

WET-PROCESSING OF KNIT FABRIC

GROUP MEMBERS:

y FURQAN ABUBAKARy KALEEM ULLAHy AWAIS IMRANy BEHZAD KHANy MUHAMMAD ABDUL MOID SAMIULLAH

SUBMITTED TO

MR. NAJAM (DM)


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CONTENTS

y INTRODUCTIONy ACKNOWLEDGEMENTy CONTENTSy TEXTILEy IMPORTANCE AND USE OF TEXTILEy WEAVING AND KNITTINGy KNITTINGy KNITTING USESy GREIGH DEPARTMENT

PRETREATMENTy SCOURINGy BLEACHINGy OBA

DYEINGy DYEING APPLICZTIONy DYEING MACHINEy CONTINUOUSy SEMI CONTINUOUSy EXHAUSTy EXHAUST IN DETAILy WINCH MACHINEy SOFT FLOW MACHINEy JET MACHINEy TURNING MACHINEy DRYER

FINISHINGy SOFT FINISHy HARD FINISHy FOLDING AND CUTTINGy CONCLUSIONy SUMMARYy SUGGESTIONy REFRENCES


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ACKNOWLEDGEMENT

CREATING THE ACKNOLEDGEMENT IS THE MOST DIFFICULT

TASK OF ANY DOCUMANTATION AND WRITING PROCESS.

WITHOUT THE HELP AND SUPPORT OF MANY DIFFERENT

INDIVISUAL EVENTS THIS DOCUMENTATION OR ANY OTHER

BOOKS FOR THESE MATTER WOULD NEVER BE

ACKNOLEDGMENT EVERY ONE ENVOLVED.

WE WILL GIVE A LITTLE TRY ANY WAY..

FIRST OF ALL WE PRAISE AND THANKS ALLAH.THE MOST

BENEFICIAL AND MOST MERCIFUL.

WE ARE GR ATFUL TO HI-KNIT P VT.LTD MILLS FOR GI VING US

THIS GREAT OPPORTUNITY TO WORK IN SUCH SUPPORTIVE

FRIENDLY ENVIROMENT. THEY HAVE GIVEN US GREAT

CHANCE TO WORK IN DET AIL.

WE ALSO WISH TO THANKS:

MR. NAJAM (DYEING MANAGER)

WE WISH TO EXPRESS OUR SINCERE THANKS TO

HOD, HASEEB-US-SALAM, MR.QAISER AND MR.YASIR

ANSARI THE DRIVING FORCE BEHIND ALL OUR WORK.


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INTRODUCTION TO TEXTILE

The word textile originates from the Latin verb texture-to weave-but, as the

textile institutes terms and definitions glossary explains, It is now a general term

applied to any manufacture from fibres, filaments or yarns characterized by

flexibility, fineness and high ratio of length to thickness.

IMPORTANCE OF TEXTILE

y We are surrounded by textiles from birth to death.y We walk on and wear textile products; we sit on fabrics-covered chairs and

sofas; we sleep on and under fabrics; textile dry us and keep us dry; they

protect us from sunlight, fire, and infection.

y Food, shelter, and clothing are basic human needs. Most clothing is made fromtextiles, and shelters are made more comfortable and attractive with textiles.

y Textiles have such an important bearing on our daily lives that everyone needsto know something about them. from earliest times, people have used textiles

of various types for covering, warmth, personal adornment, and even to

y Display personal wealth. Today, textiles are still used for these purposes andeveryone is an ultimate consumer.

USES OF TEXTILE:y Textile articles are used in every field of life.y The common used of textiles are in the form of fabric, home furnishing and

other garments.

y Clothing and furnishing textile that vary in color, design texture, an cost areaesthetically pleasing such examples are food textile, medical textile ,sports

and recreation, building material, environment and transportation.

y Textiles have been used in almost every possible context where their properties are useful. Some of the articles made from textiles are: bags and

carrying objects, balloons, kites, parachutes, clothing, flags, geo textiles, nets,

rugs, carpets and tents.


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F I B E R

y A fiber or staple fiber is a unit of matter which is usually at least 100 times longerthan it s thick

y Fibers are several thousand times longer than they are thick most apparel fibersrange in length from about 15 mm to 150mm with exception.

y A filament is a very long fiber the length of filament may range from a fewhundred M,AS in case of Silk, Several Kilometer in the case of man made fiber

y The thickness of filament tends to be similar to that of fibers.

COTTON FIBER

y The cotton fiber is obtained from plant.y It is classified as a natural, cellulosed, seed, mono cellular, staple fiber.y The density of cotton fiber 1.52 g/cm3

CHARACTERISTICS:

TENACITY : cotton fiber have good tensile strength

ELASTIC-PLASTIC NATURE :Cotton fiber is inelastic fiber

HYDROSCOPIC NATURE :Cotton is absorbent fiber

MELTING POINT :does not melt.

IGANITION TMEMPRATURE :390C.

D.P VALUE :5000

POLYMER SYSTEM :Crystalline 70%

CHEMICAL COMPOSITION :Cellulose

DIMENSIONS :Extremely long


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POLYESTER

y The word ester is the name given to salts formed from reaction betweenalcohols and acid.

y polyester is a man made, synthetic polymer, polyester filament or staple fiber.y Polyester has density1.39 g/cm3

CHARACTERISTICS:

TENACITY : Polyester filament and staple fiber are very strong.

ELASTIC PLASTIC NATURE: More elastic than plasticHYDROSCOPIC NATURE : completely hydrophobic.

MELTING POINT : 250 to 260IGNITION TEMPRATURE : unavailable.

D.P VALUE : 115 to 140POLYMER SYSTEM : extremely crystalline.

CHEMICAL COMPOSITION:polyethylene glycol terephatalate.DIMENSION : short.

TEXTILE FABRICS:

y Textile fabrics can be produced directly from webs of fibers by bonding,fusing or interlocking to make non-woven fabrics and felts, but there physical

properties tends to restrict there potential end-uses.

y The mechanical manipulation of yarn in to fabric is the most versatile methodof manufacturing textile fabrics for a wide range of end-uses.

y There are three principal method of mechanically manipulating yarn in totextile fabric: interweaving, intertwining and interloping.

1. Interweaving: is the intersection of two sets of straight threads,warp and weft, which cross and interweave at right angle to each other.

Weaving is the by far the oldest and most common method of

producing continuous length of straight-edged fabric.

2. Intertwining and twisting: includes a number of techniques, suchas braiding and knotting, where threads are caused to intertwine to

each other at right angles or some other angle. These techniques tend


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to produce special construction whose uses are limited to very specific

purposes.

3. Interloping: consist of forming yarn in to loops, each of which istypically only released after a succeeding loop has been formed and

intermeshed with it so that a secure ground loops structure is achieved.

K N I T T I N G

y Knitting is the most common method of interloping and is second only twoweaving as a method of manufacturing textile product.

y It is estimated that over seven million tons of knitted goods are producedannually throughout the world.

y Although the unique capability of knotting to manufacture shaped and form-fitting articles has been utilized for centuries. Modern technology has enabled

knitted construction in shaped and unshaped fabric formed to expend into a

wide range of apparel, domestic and industrial end-uses.

y Picturey In its simplest form, a knit fabric is made by the longitudinal and vertical

repetition of the same element, the loop, which is the basic element of the

fabric.

y The loop is a length of yarn that is forced to assume a curvilinear shape.y It can be divided in to three main sections:


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1. Loop top2. Loop side and bottom3. Half interloopy The interloop is the yarn that links two consecutive loops together.y The horizontal or vertical repetition of loops forms from the typical structure

of knit fabrics, which can be divided into weft knit fabric and warp knit

fabric.

y In weft knits the interloop links two consecutive loops placed horizontally;when one loop breaks, the entire fabric cab be undone simply by pulling the

free end of the yarn.

y In warp knits the yarn is knitted vertically or diagonally and loops are formedaccordingly; to knit the fabric, it is necessary to use many threads

simultaneously, allowing the loops formed by the different threads to bind

together.

y The knit fabric is run-proof. Therefore, the warp knit fabrics are also callednon-run or ladder-proof.

y From a physical point of view, a fabric can be described as a flexible structure,made up by the vertical and horizontal repetition of two elements: the course

and the wale.

y The word course defines a row of horizontal loops, belonging or not to thesame yarn; wale means a row of loops laid vertically one upon the other.


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Structure of st ockinet, a common knitt ed fabric. . . The meandering r ed

path defines one course, the path of the yarn through the fabric. The

uppermost white loops are unsecured and "active", but they secure the

red loops suspended from them. In turn, the red l oops secure the white

loops just below them, which in tur n secure the loops below them, and

so on.

USES OF KNIT FABRICS:

y Knit fabrics are versatile and are used to create not only clothing, but certainhome furnishing as well.

y Clothing is the most popular item to make with knits because of many varietyof knit fabric available.

y Used jersey. Which is a single knit, to make clothing with a soft, fluid design,such as dresses .T-shirts, soft jackets and coats?

y Used double knit to create jackets, coats and pants.y Interlock knits are suitable for evening wear or lingerie.y Sweater knits can used to make tops, sweaters, dresses and skirts.y Stable knits are excellent choice for curtains.\y Because knits stretch, only certain types can be used for blankets, towels and

pillows.


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GREIGH DEPARTMENT

The objectives of greigh depart are:

y MARKING AND INSPECTIONy SHEARING/CROPINGy GRADING

MARKING AND INSPECTION:y In marking and inspection the greige fabric are checked and then mark on the

fault of greige fabric by a suitable ink.

y In the inspection the mend able faults are mended by greige inspector.

SHEARING/CROPING:

y Purpose of shearing is to remove loose threads and fiber tufts on the surface ofthe fabrics otherwise it will cost mechanical damage.

y Shearing improves the surface characteristic and is especially useful forprinting that requires a fabric with a very smooth face.

GRADING:y Grading is the quality of the fabric which shows the level of faults.y The grading is done in alphabetic orders such as A, B, C.

A=excellent

B=moderate

C=poor

DEFECTS OF KNITTED FABRIC:

There are several defects produce on fabric during faulty spinning or knitting

which are given below in detail.

1. cut/hole:This fault is occurred due to machine problem.2. Snarls:This fault same as slub but this is due to excess of fibers.

3. Over twist:If two cone or bobbin yarns are mixed with each other than over twist

problem will occur.


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4. Oil spot:This fault is due to sticking of oil during knitting process.

Note:

y Any kg of fabric must not contain more than six faults.y If more than seven faults are arises then fabric will be reject.y Only six faults are allowed in thirty kg if more then six faults are occurred

then will be rejected.

y If more than two holes are arises in five kg then fabric will be rejected.y

TURNING MACHINE

This tubular turning machine is for turning tubular knit fabric before dyeing and

drying after.

y As knit fabric material is handled by the air, there is no fear of damage duringoperation.

y Made of stainless steel, the main pipe can stand up permanently withoutrusting.

y Operation is easy and safe. Air flow initiation or termination is instantlyeffected by the press of the ON or OFF push-button, or the moment the

material fabric reaches the eject roller.

y There is no lingering air consumption.


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y Air flow direction is designed to automatically switch upon alterationof the position of the curved pipe, as they are interlocked with each other

PRETREATMENT

The term pretreatment includes all operation of preparing the textile material such asknitting fabric and garments for the subsequent processes of dyeing and finishing.

OBJECTIVE OF PRETREATMENT:

y The main objective of pretreatment is to obtained uniform whitenessy

It also provides uniform absorbencyy Through pretreatment process we can obtained optimum productiony In pretreatment we remove completely seed husks.y In this process we avoid less loss of tensile strengthy Uses of qualitative chemicals provides environmental friendly process.

PROCESS OF PRETREATMENT:

There are several processes of preatment for the knit fabric before application of dyesand finishes.

1. SCOURING2. BLEACHING3. OPTICAL BRITHING AGENT

SCOURING:

y Cotton yarn and fabric contains about 8-10 % of natural impurities and knittedfabric carries additional 2-3% oily impurities from knitting machine.

y Scouring process is the process designed to remove natural fats, wax, and oilfrom the cotton fabrics using caustic (sodium hydroxide) and detergent at boil

100 centigrade for 20-30 minutes.


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OBJECTIVES:

y To remove a natural fats, wax and oil material containing in the fabricswithout damaging the fibers.

y To accelerate dye and chemical absorption of the fabrics.y To improve the handle of goods (softer).y To increase the good even absorbency.ALKALINE TREATMENT:

y In this process the fabric are treated with alkali at boiling temperature toextract out inherent impurities from substrate.

ySodium hydroxide completely breaks down proteins and pectates that amainly present in the cuticle layer of the fiber and converts these in to

water soluble products.

y The oils and fats are converted in to soap and this is turn emulsifies waxesthat are removed by washing later.

y Residues of leaves and husks are degraded but are not completely removedby hot caustic soda solution.

PROCESS ROUTE:

Fill the bath Dip the fabric Soaping

To add Caustic steaming washing

TECHANICAL DATA:

STEAM TEMPERATURE = 102-105 CENTIGRADE

STEAM TIME = 10-15 MINUTEMACHINE SPEED = 60-70 M/MINTWASHING TEMPERATURE RANGE = 80 CENTIGRADE

CHEMICALS:y CAUSTIC SODAy WETTING AGENT


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y EMULSIFIERy SEQUESTRING AGENT

BLEACHING:

y Scouring removes almost all the impurities of cotton fibers except husk andnatural coloring matter that are ultimately broken down with oxidizing agent

and then washed off the fabric.

y The oxidation treatment or bleaching is necessary for producing white goodseither as a finished prodect or dyeing pastel shades. Even for dark shade

bleaching improve the brilliance and evenness of the shade.

y To increase the degree of whiteness.

BLEACHING WITH HYDROGEN PEROXIDE:

y The oxidizing agent most commonly used today for bleaching of textile ishydrogen peroxide.

y Loss less of weight (D.P)y Easy Operation.y Hydrogen peroxide is a weak acid.

ADVANTAGE OF HYDROGEN PEROXIDE BLEACHING:

y The advantage of peroxide over the hypochlorite is lower loss in weight or theprocessed goods.

y It reduced oxidative damage and economy in use of water and consequentlylesser cost of effluent treatment

CHEMICAL REACTION:

H2O2 + OH=H2O+OOH

OOH = OH + [O] bleaching stage


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2H2O2 = 2H2O +O2

PROCESS ROUTE:

Fill the bath Dip the fabric Soaping

To add Caustic To add H2O2 steaming washing

TECHANICAL DATA:

STEAM TEMPERATURE = 102 -105 CENTIGRADE

STEAM TIME = 10 -15 MINUTEMACHINE SPEED = 60 -70 M/MINTWASHING TEMPERATURE RANGE = 80 CENTIGRADE

CHEMICALS:

y HYDROGEN PEROXIDEy WETTING AGENTy SODIUM HYDROXIDEy SEQUESTRING AGENTy STABILIZER

OPTICAL BRIGHTNING AGENT:

y Fluorescence is the ability of a substance to absorb radiation and to re-radiateit at a longer wave length.

y They convert ultra-violet radiation present into visible light at the blue end ofthe visible spectrum.

y OBAs are exposed to UV fluorescing light bulbs, Black Light, the objectsglow in the dark.

y A sure fire way of identifying fibers that are treated with optical brighteners.y Fluorescent brightening agents are available for all the major fiber types.y They are applied by methods very similar to dyeing techniques.


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MECHANISM OF OBAS:

The following diagram shows that conversation of invisible light like UV into visiblelight.

APPLICATION

y It can be applied at bleaching stage.y PH Range is high (4-11)y We add OBAs in the chemical bath to increase the whiteness of the fabric

Till 130o

Burger whiteness .


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DYEING

y Dyeing is the process to colors the textile materials of one shade.y Textile dyeing is concerned with organic (that is, carbon-based) compounds

that can be dissolved in appropriate solvents, usually water.

y The dyes in solution are absorbed on the surface of the textile fibre then passinto the interior of the material by a process called diffusion.

The process of transferring the dye from solution to the fibre is called

exhaustion, with 100% exhaustion meaning that there is no dye left in the

dyebath solution.

y An important property of a dyeing is its levelness, in other words when thesame depth of colour can be seen all over the material

MECHANISM OF DYEINGThere are three mechanism of dyeing process.

y Exhaust dyeingy Semi continuous dyeingy Continuous dyeing

EXHAUST DYEING:

y A limited quantity of fabric runs in the processing machine for a certain periodof time till the completion of chemical reaction.

y For examples winch, jet, softflow.y Each load of fabric is called batch.y The next batch can not be started until the first batch is completed a bad

removed.

y Exhaust dyeing is very suitable for knitted fabrics.KEYS OF CHEMICAL REACTION:

1. TIME2. TEMPERATURE3. PH


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DYE:

yA dye or dyestuff may be defined as a colored organic compound which isused for imparting colors to a substrate.

y The chromospheres, the colored portion of the dye molecules.y The auxochrome is a second portion of dye molecule which makes the dye

soluble and is a site for bonding to the fiber.

CLASSES OF DYES:

REACTIVE DYE

y Among the different classes of dyes for the cellulosic fibers thereactive dyes only ones that attached to the fibers by covalent bond and

get there name for the same reason.

y Introduced in 1956 porcine dye by ICI, UK. y Water soluble dye stuff having anionic nature.y Mainly consumed for cellulosic dyeing.y It gives excellent washing fastness.y It also gives well to excellent light fastness.y Excellent shade range.y It is sensitive to chlorine bleached,

GENERAL STRUCTURE OF REACTIVE DYE:

S-D-B-RG-X

Where,

S = soloubilising group

D = dye chromogen

B = Bridge linking group

RG = reactive group

X = leaving group


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APPLICATION OF REACTIVE DYES:

1. Lubricating agent/Anti creasing agent.2. Dispersing/Leveling agent3. Salt4. Dye stuff5. Alkali6. Lubricating/ anti creasing agent7. Acetic acid8. Soaping9. Acetic acid

PROCEDURE:

y Fill and prepare the bath by the addition of (1) and (2). y Introduction fabric in the bath and then run for 5-10 mint.y Add salt at 50 OC and run for 10-15 min.y Add the dye solution and raise the temperature till 60 OC at the same

time migration and penetration start.

y Add alkaliy Run for 30-60 min.y Add alkaliy Run for 30-60 miny Check shade and drain watery Fill and cold rinsey Drain and again Rinsey Add acetic acid and run for 10 miny Add soap and raise the temperaturetill boily Cool down and rinse

DISPERSE DYE:

y Disperse dye applied on polyester.y Disperse dyes are insoluble in water.y Disperse dyes have number of dispersing agent.y It is non-ionic in nature.


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y Dyeing of polyester is done by trappening of the dyes in the structureof fabric.

y Sublimation fastness is an important property of disperse dyes.y Dyeing of polyester is impossible less than 85 centigrade because Tg

(glass transition temperature) of polyester is around 85-90 centigrade.

y Fair to excellent light fastness and wash fastness.

APPLICATION OF DISPERSE DYE

1. Acid buffer2. Leveling agent3. Lubricating agent4. Dispersing agent5. Dye stuff

PROCEDURE

y Fill and prepare the bath by the addition of (1) and (2). y Introduction fabric in the bath and then run for 5-10 mint.y Add the dye solution and raise the temperature till 50 OC at the same

time migration and penetration start.

y Add (2) and (4)y To raise the temperature at 130 OCy Run for 30-60 min.y To gradually cool down the temperature by 2 OC gradienty Check shade and drain watery Fill and cold rinsey Drain and again rinsey After rinsing to want to improve the fastness properties of disperse

dyes RC (Reduction Cleaning) is done.

y For 20 min at 80 OCy Add soap and raise the temperaturetill boily Cool down and rinse


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DYEING MACHINES

The basic requirements of a dyeing machine may be summarized into the followingessentials

1. That it shall provide sufficient movement for the liquor to penetrate uniformlyinto every part of the goods.

2.

Although the movement must be sufficient to bring about penetration it mustnot be so vigorous that it will damage finer materials or cause milling of

woolen goods.

3. The machine must be constructed of a material which will withstandprolonged boiling with acid or alkaline solutions.

4. The heating arrangements must be such that a comparatively uniformtemperature will maintained throughout the liquor.

5. There should be some means of adding the concentrated dyestuff solution insuch a way that it becomes will diluted before it comes into contact with the

goods.

6. All moving parts and electric motors should be protected against the corrosiveaction of steam and acidic atmospheric conditions

Other features which are desirable are:

(a) The largest possible outlet and water-inlet valves, because a considerableproportion of the dyeing cycle is take up with filling and empting, especially

when several rinses are required.

(b) A closed steam coil through which cold water can also be circulated. Thismakes it possible to dye without alteration of liquor ration due to

condensation of steam. It also allows the liquor to be cooled before the

addition of dyes for shading, encouraging, in many cases, the use of faster

colors for final matching.


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(c) Some automatic temperature=control device, preferably designed to regulatethe rate at which the liquor is brought to the boil or to any other

predetermined maximum temperature.

W I N C H:

The winch machine is one of the oldest dyeing equipment and is stillpopular because of low capital cost, simplicity in operation and versatility

in use for different operations and different types of fabrics.

Compared with jigger, there is less lengthwise tension on the fabric and sothe winch can be used for knit fabrics made from all type of fibers and

woven fabrics of wool and man-made fibers.

Principle of the winch machine is to circulate a number of loops or endlessropes (15 to 40) of fabric of equal lengths that are lying in the dye bath but

are continuously pulled out and then returned to it with the help of circular

or elliptical winch.

The liquor is contained in a stainless steel vat, usually having a depth of2.5 meters, height of 1 meter and length varying between 3 to 4 meters.

The backside of the vat is not vertical but is sloping at an angle of about 45

degree so as to facilitate sliding of the frpes and also to reduce volume of

the processing liquor.

To avoid entanglement, a peg rail, fitted below a fly or jockey roller infront of the machine, separates the fabric ropes. The fabric ropes rotate at a

speed of 60 to 70 meters per min.

A salting box is provided in front of the machine by interposing aperforated steel sheet at a distance of 30cm from the front of the dye bath.

Water and steam pipes and a drain valve are also provided in thiscompartment.


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Simply pulling a lift rod operates the train valve. Fabric pieces are loadedmanually but are unloaded with the help of a mobile set of squeeze rollers

after tieing together different ropes of fabric into a continuous length.

The liquor-goods ration of the winches varies from 12 to 20 and isadjusted according to the requirement. The machines are generally totally

enclosed to get a relatively higher temperature and to avoid steam in the

dye house atmosphere.

Modern machines are also fitted with controls to regulate temperature ofdye bath and duration of a process.

TECHANICAL DATA:

LIQUOR RATIO = 1:8

TEMPERATURE = 102 -105 CENTIGRADE

SPEED = 60 -70 M/MINT

FABRIC CAPACITY = 64-70 KG

WATER CAPACITY = 500 LITRE


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JET DYEING MACHINE

In this system, the fabric was rotated at a high speed of about 400meters per min through a circular tube with the help of the

circulating dyeing liquor.

The liquor is collected from bottom of the machine, passed througha high-volume centrifugal pump and a heat-exchanger and then

injected into a tube a top of the machine along with the fabric.

Principle of the jet dyeing is considered a revolutionarydevelopment in the design of the rope-dyeing machines. As it often

happens that once an idea is successfully established, many

evolutionary developments take place in rapid succession to

improve the original invention.

TECHANICAL DATA:

LIQUOR RATIO = 1: 10

TEMPERATURE = 130 CENTIGRADE

SPEED = 400 M/MINT

FABRIC CAPACITY = 300 KG



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SOFT FLOW JET DYEING MACHINE

Flow machine is that in the latter fabric is positively lifted from the bath with adriven reel and then carried to the far end of the machine by the jet of the dye

liquor

The great expansion in the demand for crimples fabrics inspired the machinebuilder. To seek a better design for dyeing machine.

Winches have certain deficiencies such as.1. long liquor ratio2. risks of tangling3. difficulty in maintaining uniform temperature4. elongation of the fabric due to tension5. Formation of creases.

All these disadvantages were surmounted by the jet machine.

As the rate of flow of the liquor is lower than the jets of earlier models, themachine is termed soft-flow.

Dye additions are made through a secondary pressure pump when operatingabove 100

oC.


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As the fabric is lifted with a driven reel, the lengthwise tension and consequentcreasing on it is minimized.

The soft-flow jets were again modified when oil prices quadrupled in 1974-5and the low-liquor-ratio machine were introduced in order to economizer on

energy.

A large variety of machines were developed on this consideration in both thelong and circular types.

To further reduce tension for crease-sensitive fabrics, M/s this introducedRotor-Stream machine in which fabric is dropped in a rotating drum that

rotates the fabric positively instead of being pushed by load of fabric on top of

it.

It is also customary now Teflon (PTFE) Sheet or rods shoes smooth surfaceallows the fabric to move forward with a minimum of drag resistance.

For knit fabric, some machine manufacturers (Slaves) provided an air-ballooning device fitted before the lifting reel so that the creases in the tubular

fabric are removed continuously and so dyeing is free of the crease-marks.

The Liquor ratio in the jets is usually around 10-8:1. However in modern jetsespecially those required for the cotton goods, the trend is to reduce the liquor

ratio still more so as to conserve steam and chemicals and also to reduce

effluent.

M/s then has introduced an air/steam transportation device to propel thefabric-rope in the dyeing tube. This machine is claimed to have liquor ratio, as

low as 3:1 for cotton goods and 2:1 or even less for the synthetic fibers.


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SOFT FLOW

TECHANICAL DATA:

LIQUOR RATIO = 1: 6

TEMPERATURE = 102 -105 CENTIGRADE

SPEED = 200 M/MINT

FABRIC CAPACITY = 300-400 KG


DRYING OF KNITS FABRICS

y The knits goods, in contrast to the woven cotton fabrics, are easily starchedand their loops would get distorted under the stretching tension of the dying

cylinders.

y Special drying machines have, therefore , been developed to dry knitwear withthe minimum of tension.

y In one simple system, the knitted tubes are slipped over perforated steel pipesand then hot air is blown through the perforations while the fabric is gradually

pulled up at a rate consistent with adequate drying.


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y This equipment has a low capital cost but in labor intensive and the finishedfabrics gets slightly starched.

y More desirable results are obtained by carrying fabric on a fiber-glass orpolyester mesh conveyer belt into a chamber in which hot air is blown on both

sides of the fabric alternately.

y The fabric is slightly buffeted during the drying operation and a tension-freefabric with a lofty handle is obtained


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DRYING OF KNITS FABRICS

y The knits goods, in contrast to the woven cotton fabrics, are easily starchedand their loops would get distorted under the stretching tension of the dying

cylinders.

y Special drying machines have, therefore , been developed to dry knitwear withthe minimum of tension.

y In one simple system, the knitted tubes are slipped over perforated steel pipesand then hot air is blown through the perforations while the fabric is gradually

pulled up at a rate consistent with adequate drying.

y This equipment has a low capital cost but in labor intensive and the finishedfabrics gets slightly starched.

y More desirable results are obtained by carrying fabric on a fiber-glass orpolyester mesh conveyer belt into a chamber in which hot air is blown on both

sides of the fabric alternately.

y The fabric is slightly buffeted during the drying operation and a tension-freefabric with a lofty handle is obtained


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FINISHING

y Textile finishing is a term commonly applied to different process that thetextile material under go after pretreatment, dyeing or printing for final

embellishment to enhance there attractiveness and sale appeal as well as for

comfort and usefulness.

y The finishing treatment are basically meant to give the textile material certaindesirable properties like softness, luster, pleasant handle, drape, antistatic,

non-slip, soil-realsed etc.

CLASSIFICATION OFFINISHING:

The finishes are softening sub divided as physical and chemical, permanent and

temporary, deposition and reactive etc.

MECHANICAL FINISHES:

y PEACH FINISH

CHEMICAL FINISHES:

TEMPORARY:

y SOFT FINISHy NORMAL FINISHy HARD FINISH

PERMANENT:

y SOFT FINISHy RESIN FINISH


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MECHANICAL FINISHES

PEACHING:

y The main aim of the peaching is to lift a layer of fibers and thus create a pileof loose fibers on the surface of the fabric.

y The pile maintains a stationary layer of air that is a good insulator and thusprotects the wearer of the peach fabrics from the cold in winter season.

y The peaching process also gives a lofty and soft handle.y The speed of machine is varies from 12 to 15 meters per minute.

CHEMICAL FINISHES

Term chemical finishing is commonly used to differentiate it from the mechanical

finishes and implies use of chemicals, with or without the physical treatment, to

achieve certain end result.

SOFT FINISH:

Softening is the complex phenomenon and is composite of surface smoothness and

internal lubrication of the fiber elements of the treated fabric.

There are many softening agent used in industries such as:

y WETTING AGENTy ACETIC ACID (FOR NEUTRALIAZATION)y NON-IONIC POLYETHYLENE SOFTNERy SLIGHTLY CATIONIC SOFTNERy SILICON SOFTNER


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PHYSICAL TESTING

In this department we check the fabric by physical treatment and determined the net

result of the fabric such as.

y FINISH WIDTHy RUBBING FASTNESSy LIGHT FASTNESSy WASHING FASTNESSy PILLING FASTNESSy SHRINKAGE FASTNESSy TENSILE STRENGTHy

GSMy TEAR STRENGHT

FINISH WIDTH:y First we check the finish width of fabric through measurement scale.y If original width is not achieved then we cold down in testing room at 21 OC

for 4 hour for bringing original length.

RUBBING FASTNESS:

There are two types of rubbing fastness.y DRY FASTNESSy WET FASTNESS

DRY FASTNESS:y First we take sample in to crock meter.y In crock meter there is finger on which we fixed 100% dry cotton piece

through rubber and then apply a load on sample and give it 10 cycles.

WET FASTNESS:y First we take sample in to crock meter.y In finger of crock meter we fixed 65% wet cotton piece through rubber and

then apply load on it for 10 cycles.


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LIGHT FASTNESS:

Light fastness is the degree to which a dye resists fading due to light exposure.

y First we cut all design from the fabric for testing the light fastness.y Now cutted design are fixed with different strip, then it fixed in light fastness

machine in which one area is exposed and other is hidden against Xenon alpha

for 20 hour.

WASHING FASTNESS:y First we cut the same design for the testing of washing fastness and take 2

pieces.

y We punch multiples fibers such as cotton, nylon, acrylic, acidic, wool, silk etcwith fabric.

y In washing machine we use 150 ml solution of detergent and there are steelballs for few minutes.

PILLING FASTNESS:y In pilling we rub the same fabric with each others for 2000 cycle in pilling

machine.

y Due to friction pilling effect is produce on fabric.

\SHRINKAGE:y In shrinkage test we check the shrinkage % of the fabric by a specific method.y

We cut the sample from weft or warp and after it mark with shrinkage scale onsample from back side of fabric.

y After marking we wash the fabric in to washing machine with 2 bowls.y After each washing we determined the shrinkage % of fabric by shrinkage %

scale.

TENSILE STRENGHT:y In this testing we check the tensile strength of sample by applying a force on

warp or weft sides.

y The force intensity depends on the fabric quality.y After applied a force on fabric we also check the extension of warp or weft.

GSM:y GSM is expressed as gram per square meter.y We determined the GSM pg fabric by GSM cutter and after cutting the cutted

fabric weighted on physical balance.


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TEAR STRENGHT:y In this testing we determined the tear strength by applying a force on both side

of the fabric, and check reading on screen of the machine.

FINISH FABRIC

There are three objectives of this department such as

1. CUTTING2. STITCHINg3. DELIVERY

CUTTING:

y In cutting the finish fabric is come for cutting according to requirement of thecustomer.

y The cutting should be in proper way other wise fabric may be reject by buyer.y The finished fabric department gives the plan of cutting to the cutting

department according to the customer requirement.

y There are two styles of cutting.1. Manually2. Aotomatic

STITCHING:

y After cutting pf the finish fabric is come to stiching department for cutting.y In stiching we joined two fabric together.

DELIVERY:

y After cutting and stitching the articles are ready for delivery to the customer.y In delivery first the fabric is passed through metal dectector machine in which

any metal is detected because the final article should be free from any default.


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y The packing should be proper and the tag of company should be stamed.

HYDRO EXTRACTOR

y Working width 1300mmy Machine speed 5~30M/miny Machine for the hydro extractor, softener, air ballooning type of cotton

knitted tubular fabrics without tension, with fabrics entwisting, air balloon,

control of the squeezing pressure and control of the final width of the fabric.

y Automatic control of the feeding without tension, no edge mark, final foldingwithout stretching. Versions with simple or double squeezing and imbuing

with softeners.

ADVANTAGES TO HYDROEXTRACTOR:

y No deformation of the packages.y Excellent rewinding properties. Rewinding can even be eliminated in a lot of

cases.

y Low residual moisture.y Even humidity distribution through the package.y Low energy consumption.


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y Dyeing tubes last longer.y Processes many different size packages.y Operator of centrifuge can also load dryer.y Maintenance-free brakes.y Closed system for effluent.y Low compressed air consumption.y Significant energy savings


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CONCLUSION:

HI-KNIT IS CLEAR THE FIRST CHOICE OF EVERY ONE WHO

BELIEVES IN QUALITATIVE APPROACH OE TEXTILE

MATERIAL AN ENVIRONMENT OF HIGHLY RESPONSIBLE

PEOPLE AND COUNTRY.HI-KNIT IS ENJOYING HEALTHY

MARKET SHARE AND TASTE OF GOOD STATUS IN TERMS OF

ITS OPERAVTIVE FEATURES AND CUSTOMER SUPPORT.HI-

KNIT IS CLEARLY THE BEST INDUSTRY IN PAKISTAN.

BETTER SERVICES ASD PRODUCTION OF HI KNIT

EXPERIANCING A GOOD REASONABLE M ARK UP WITH

ASSUARANCE OF SATISFICATION AND SUPPORT . HI-KNIT HAS

MORE CUSTOMER AS COMPARE TO OTHER INDUSTRIES,IF

THEY GIVEN PROPER ATTENTION ON EVERY CUSTOMER THEN

IN FEW YEARS IT WILL BE THE LEADING INDUSTRY OF

TEXTILE IN PAKISTAN.


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SUGGESTION:

The main purpose of any textile is to produce acceptable quality

product and completive acceptable price. In order to complete in

markets the efficiency of processing used in wet processing should

be developed thoroughly which is only colony be possible by

controlling the proven variable.

There are some suggestions which we were observed in HI

KNIT and we hope you will consider these suggestions on the

priority bases in the industry.

y To install proper temperature and pressure gauges in eachmachines, to know the actual value of temperature and

pressure which alternatively reduce the cost of energy and

improved chemical process.

y To control the steam leakage in the pipes properly, toovercome the high steam consumption and maintain the

working area temperature as well.

y To reduce the process ti me by the proper dosing of chemicalsand give a proper attention to

y There should be proper maintenance of each processingmachine at the end of the month tso enhance the life of

machine and their parts as well.

y There should be continual improvement to shift the industryfrom conventional methods to modern high quality

productive methods with the addition of highly professional

technical staff


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36082260 knit fabric processing[1]

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